Multi-chip package and method for manufacturing the same

ABSTRACT

A multi-chip package structure is provided, including a substrate having a grounding structure; two semiconductor elements disposed on and electrically connected to the substrate; an encapsulant formed on the substrate and encapsulating semiconductor elements, wherein the encapsulant has a plurality of round holes formed between the semiconductor elements; and an electromagnetic shielding structure formed in each of the round holes and connected to the grounding structure to achieve electromagnetic shielding effects. A method for forming the multi-chip package is also provided.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims under 35 U.S.C. §119(a) the benefit of TaiwaneseApplication No. 102105957, filed Feb. 21, 2013, the entire contents ofwhich is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to semiconductor package structures, and,more particularly, to a multi-chip package and a method formanufacturing the same.

2. Description of Related Art

With the development of the electronic industry, electronic products atthe market have demands for light weights, compact sizes, high speeds,and multifunctions. Therefore, a multi-chip package inside the productdevelops toward to a high computation speed, high component density, andhigh complexity, and further integrates other electronic componentshaving multifunctions such as biology, optics, mechanics, electronics,and magnetics in one package.

In order to accord with the trend of a low-profiled and compact-sizedmulti-chip package, system in package (SiP) thus develops a multi-chipmodule (MCM) package structure. However, this structure increases thedensity of components and causes the electromagnetic interference (EMI)between chips disposed on the same substrate.

For preventing the EMI between chips, presently the industry develops amulti-chip package having an electromagnetic shielding function. Asshown in FIGS. 1A and 1B, a conventional multi-chip package 1 having anelectromagnetic shielding function comprises: a substrate 10 having twosemiconductor elements 11 a and 11 b disposed thereon and electricallyconnected thereto, an encapsulant 12 formed on the substrate 10, a longtrench 120 formed in the encapsulant 12 and formed between the twosemiconductor elements 11 a and 11 b, and an electromagnetic shield 13formed in the long trench 120 and electrically connected to a groundingstructure 100 of the substrate 10. In addition, a plurality ofelectromagnetic shield bars 13′ are formed in the encapsulant 12, asshown in FIG. 1B′.

However, the conventional long trench 120 is formed by a laser method,and the encapsulant 12 will be overheated if the laser is performed fora long time, causing damages of the semiconductor elements 11 a and 11 bor a warpage of the encapsulant 12.

Further, it takes long time to form the long trench 120, which causes anincrease of the manufacturing cost.

Therefore, how to overcome the mentioned problems of the prior art issubstantially an issue desirably to be solved.

SUMMARY OF THE INVENTION

In view of the above-mentioned problems of the prior art, the presentinvention provides a multi-chip package, comprising: a substrate havinga grounding structure; two semiconductor elements disposed on andelectrically connected to the substrate; an encapsulant formed on thesubstrate and encapsulating the semiconductor elements, wherein theencapsulant has a plurality of round holes formed between thesemiconductor elements; and an electromagnetic shielding structureformed in each of the round holes and connected to the groundingstructure.

The present invention further provides a method for manufacturing amulti-chip package, comprising: forming an encapsulant on a substratehaving two semiconductor elements disposed thereon such that thesemiconductor elements are embedded in the encapsulant, wherein thesubstrate has a grounding structure; forming a plurality of round holesdisposed between the semiconductor elements and penetrating theencapsulant; and forming an electromagnetic shielding structure in eachof the round holes and connecting the electromagnetic shieldingstructure to the grounding structure.

The present invention further provides a multi-chip package, comprising:a substrate having a grounding layer; two semiconductor elementsdisposed on and electrically connected to the substrate; an encapsulant,formed on the substrate and encapsulating the semiconductor elements,wherein the encapsulant has a plurality of round holes disposed betweenthe semiconductor elements and penetrating the encapsulant andsubstrate; and an electromagnetic shielding structure formed in each ofthe round holes and connected to the grounding layer.

The present invention further provides a method for manufacturing amulti-chip package, comprising: forming an encapsulant on a substratehaving two semiconductor elements disposed thereon such that thesemiconductor elements are embedded in the encapsulant, wherein thesubstrate has a grounding layer; forming a plurality of round holesdisposed between the semiconductor elements and penetrating theencapsulant and substrate; and forming an electromagnetic shieldingstructure in each of the round holes and connecting the electromagneticshielding structure to the grounding layer.

In an embodiment, the round holes are formed by a laser drilling method.

In an embodiment, the methods further comprise forming a strip hole inthe encapsulant, wherein the strip hole and the round hole are spaced atan interval, and the electromagnetic shielding structure is furtherformed in the strip hole.

In an embodiment, the methods further comprise forming a heatdissipating element on the encapsulant, and thus the multi-chip packagehas a better effect of heat dissipation.

From the above, the multi-chip packages and the methods formanufacturing the same of the present invention shorten the time of thelaser drilling by forming round holes, and avoid drawbacks such as anoverheated encapsulant, a warpage or a damage of the semiconductorcaused by a long processing time.

Moreover, compared with the conventional long trench, the round holes ofthe present invention have a process with shorter time, and thus reducethe manufacturing cost.

Furthermore, because a heat dissipating element is disposed on theencapsulant of the multi-chip package of the present invention, theelectromagnetic shielding structure of the present invention can notonly provide an effect of electromagnetic shielding, but alsoeffectively transmit heat generated during the operation of asemiconductor to a heat dissipating element to provide an excellent heatdissipation effect for the multi-chip package of the present invention.

BRIEF DESCRIPTION OF DRAWINGS

The invention can be more fully understood by reading the followingdetailed description of the preferred embodiments, with reference madeto the accompanying drawings, wherein:

FIGS. 1A and 1B′ are schematic views of a multi-chip package accordingto the prior art, wherein FIG. 1B is a top view of FIG. 1A, and FIG. 1B′is a top view of another pattern of FIG. 1A;

FIGS. 2A-2C are cross-sectional views illustrating a method formanufacturing a multi-chip package according to the present invention,wherein FIG. 2B′ is a top view of FIG. 2B, and FIG. 2B″ is anotherembodiment of FIG. 2B′;

FIG. 3 is a cross-sectional view of another embodiment of a multi-chippackage according to the present invention; and

FIG. 4 is a cross-sectional view of another embodiment of a multi-chippackage according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following illustrative embodiments are provided to illustrate thedisclosure of the present invention, these and other advantages andeffects can be apparently understood by the in the art after reading thedisclosure of this specification. The present invention can also beperformed or applied by other different embodiments. The details of thespecification may be on the basis of different points and applications,and numerous modifications and variations can be devised withoutdeparting from the spirit of the present invention.

It should be advised that the structure, ratio, and size as illustratedin this context are only used for disclosures of this specification,provided for persons skilled in the art to understand and read, andtechnically do not have substantial meaning. Any modification of thestructure, change of the ratio relation, or adjustment of the sizeshould be involved in the scope of disclosures in this specificationwithout influencing the producible efficacy and the achievable objectiveof this specification. Also, the referred terms such as “on”, “one” and“two” in this specification are only for the convenience to describe,not for limiting the scope of embodiment in the present invention. Thechanges or adjustments of relative relationship without substantialchange of technical content should also be considered within thecategory of implementation.

FIGS. 2A-2C are cross-sectional views illustrating a method formanufacturing a multi-chip package according to the present invention.

As shown in FIG. 2A, a substrate 20 having two semiconductor elements 21a and 21 b disposed thereon and electrically connected thereto isprovided, and an encapsulant 22 is formed on the substrate 20 andencapsulating the semiconductor elements 21 a and 21 b such that thesemiconductor elements 21 a and 21 b are embedded in the encapsulant 22.

In an embodiment, the substrate 20 has a grounding structure 200 and agrounding layer 201 connected to the grounding structure 200, and thesemiconductor elements 21 a and 21 b are chips.

Moreover, there are various types of the substrate 20 that arewell-known by persons skilled in the art, further description herebyomitted.

Furthermore, the encapsulant 22 is also well-known by persons skilled inthe art, further description hereby omitted.

In an embodiment, the semiconductor elements 21 a and 21 b areelectrically connected to the substrate 20 by, but not limited to,bonding wires (not illustrated) or conductive bumps (not illustrated).

As shown in FIGS. 2B and 2B′, a plurality of round holes 220 penetratingthe encapsulant 22 are formed between the semiconductor elements 21 aand 21 b, and at least one of the round holes 220 exposes the groundingstructure 200.

In an embodiment, an intersectional region A is defined between thesemiconductor elements 21 a and 21 b. The round holes 220 are formed inthe intersectional region A by the laser, and the round holes 220 arespaced apart from one another.

In another embodiment, a plurality of strip holes 220′ are formed in theintersectional region A of the encapsulant 22, and are spaced from theround hole at an interval, as shown in FIG. 2B″.

Moreover, no specific limitation is placed on the order of forming theround holes 220 and strip holes 220′. Preferably, the round holes 220are formed after the formation of the strip holes 220′.

Furthermore, no specific limitation is placed on the method of formingthe round holes 220 and strip holes 220′. For example, a regular laserdrilling method satisfies the requirement.

Because the method of the present invention does not apply a continuouscutting method, the warpage issue occurred when the encapsulant 22 isoverheated during the laser drilling can be prevented. The drawback ofthe increasing manufacturing cost caused by the defects due to anoccurrence of a damage can therefore be prevented.

As shown in FIG. 2C, which continues the process of FIGS. 2B and 2B′, anelectromagnetic shielding structure 23 is formed in each of the roundholes 220, and is connected to a grounding structure 200 of thesubstrate 20 to manufacture a multi-chip package 2.

In an embodiment, the electromagnetic shielding structure 23 is made ofa conductive paste containing metal, copper or solder. Theelectromagnetic shielding structure 23 is electrically connected to thegrounding structure 200 of the substrate 20 for shielding and protectingthe semiconductor elements 21 a and 21 b from being affected by the EMI,to achieve the effect of electromagnetic shielding.

In an embodiment, the process of FIG. 2B″ is continued, and theelectromagnetic shielding structures 23 are further formed in the stripholes 220′, and are thus electrically connected to the groundingstructure 200 or the grounding layer 201.

A multi-chip package 2 according to the present invention comprises asubstrate 20 having a grounding structure 200, two semiconductorelements 21 a and 21 b disposed on and electrically connected to thesubstrate 20, an encapsulant 22 formed on the substrate 20 andencapsulating the semiconductor elements 21 a and 21 b, a plurality ofround holes 220 disposed between the semiconductor elements 21 a and 21b, formed in the encapsulant 22 and exposing the grounding structure200, and an electromagnetic shielding structure 23 formed in each of theround holes 220 and connected to the grounding structure 200.

FIG. 3 is another embodiment of a multi-chip package 3 according to thepresent invention. A heat dissipating element 24 is formed by forming ametal film using a plating method or by attaching a metal sheet on theencapsulant 22, and is effective to dissipate the heat generated duringthe operation of the semiconductor elements 21 a and 21 b.

In an embodiment, the electromagnetic shielding structure 23 formed ineach of the round holes 220 is connected to the heat dissipating element24.

Since being made of a conductive paste containing metal, copper, orsolder, the electromagnetic shielding structure 23 has a well heatconductivity and can effectively transmit the heat to the heatdissipating element 24. Therefore, a good effect of heat dissipation forthe multi-chip package 3 is achieved.

FIG. 4 is another embodiment of a multi-chip package according to thepresent invention. A round hole 220″ penetrates the encapsulant 22 andthe substrate 20 and is directly connected to a grounding layer 201 ofthe substrate 20.

In summary, with a design of forming an electromagnetic shieldingstructure in a round hole, the multi-chip package and method formanufacturing the same according to the present invention not only speedup the process and reduce the manufacturing cost, but also overcomedrawbacks of the prior art, such as a warpage of the encapsulant or adamage of the chip.

The foregoing descriptions of the detailed embodiments are onlyillustrated to disclose the features and functions of the presentinvention and not restrictive of the scope of the present invention. Itshould be understood to the in the art that all modifications andvariations according to the spirit and principle in the disclosure ofthe present invention should fall within the scope of the appendedclaims.

What is claimed is:
 1. A multi-chip package, comprising: a substratehaving a grounding structure and a grounding layer, wherein thegrounding structure penetrates the substrate, and the grounding layerextends to the grounding structure and connects vertically to thegrounding structure; two semiconductor elements disposed on andelectrically connected to the substrate; an encapsulant formed on thesubstrate and encapsulating the semiconductor elements, wherein theencapsulant has a plurality of round holes formed between thesemiconductor elements; and an electromagnetic shielding structureformed in each of the round holes and connected to the groundingstructure.
 2. The multi-chip package of claim 1, wherein the encapsulantfurther has at least one strip hole, and the at least one strip hole andthe round holes are spaced at an interval.
 3. The multi-chip package ofclaim 2, wherein the electromagnetic shielding structure is furtherformed in the at least one strip hole.
 4. The multi-chip package ofclaim 1, further comprising a heat dissipating element formed on theencapsulant.
 5. A multi-chip package, comprising: a substrate having agrounding layer extending horizontally through the substrate, wherein agrounding structure penetrates the substrate, and the grounding layerextends to the grounding structure and connects vertically to thegrounding structure; two semiconductor elements disposed on andelectrically connected to the substrate; an encapsulant formed on thesubstrate and encapsulating the semiconductor elements, wherein theencapsulant has a plurality of round holes penetrating the encapsulantand substrate and formed between the semiconductor elements; and anelectromagnetic shielding structure formed in each of the round holesand connected to the grounding layer.
 6. The multi-chip package of claim5, wherein the encapsulant further has at least one strip hole, and theat least one strip hole and the round hole are spaced at an interval. 7.The multi-chip package of claim 6, wherein the electromagnetic shieldingstructure is further formed in the at least one strip hole.
 8. Themulti-chip package of claim 5, further comprising a heat dissipatingelement formed on the encapsulant.